Aiming to dramatically slash costs, Time Inc. will lay off roughly 540 employees starting next week, company insiders say.

The cuts will be staggered over two weeks and wrap up right before Thanksgiving so that the magazine publisher can take a charge against earnings in the fourth quarter.

Layoffs are expected to be 6 percent of the workforce, which is now estimated to have shrunk to 9,000 employees worldwide. But even that number is not finalized and could end up bigger.

Last year, the company cut 600 people (or 6 percent) from its 10,000 employees and took a charge against earnings of $176 million.

The News and Finance Group, which includes Time, Sports Illustrated, Fortune, Fortune Small Business and Money, is expected to be the hardest-hit part of the company. The unit will have a small reprieve: under a contract with the Newspaper Guild the company will first have to seek buyout volunteers.

The London-based IPC Group and the Birmingham, Ala.-based Southern Progress, whose flagship title is Southern Living, escaped major hits in the round of layoffs unveiled in the fourth quarter of last year. The division, headed by Executive Vice President Sylvia Auton, will not be so lucky this time around, sources predicted.

The scale of the layoffs means Time Inc. holds the distinction of the biggest mass firing in publishing this year, outpacing the 460-plus involuntary terminations at rival Condé Nast.

Time Inc. CEO Ann Moore and Editor-in-Chief John Huey are keeping the total number they aim to cut quiet. Insiders now say they may opt to go the Condé Nast route and not reveal the total number at all, despite the bad publicity Condé racked up over four weeks of layoffs.

In the areas covered by the union agreement, if Time Inc. doesn’t get sufficient volunteers after two weeks to meet its target cuts, then the involuntary firings will begin. There is nothing to prevent the company from instituting cuts immediately in areas not covered by the agreement.

People and Entertainment Weekly are among the magazines covered by the Guild contract, but most of the other titles, such as InStyle and Real Simple, are not.

The company has not opened any negotiations with union representatives, which indicates that it won’t offer any sweeteners for voluntary departures.

“We haven’t had any discussion this time around,” said Bobby Townsend, the Newspaper Guild representative at Time Inc. “Sometimes we don’t get a lot of advance notice before layoffs are announced.”

Last time around, the union was told about the firings less than 24 hours before they were announced.

The Guild contract provides laid-off employees with two weeks of pay for each year of service, plus some slightly larger packages for employees of 20 or 25 years.

The Guild unit at Time Inc. has shrunk to just 300 members, but often the pay and severance packages are used as the benchmark for the non-unionized US-based workers in other areas of the company, as well.